When the Red Ninjas from GI Joe Retaliation hit the shelves last year, I found myself interested in the Ninja side of the GI Joe mythos for the first time. So I'm slowly adding a few custom ninjas to my collection, like Slice. I loved the Nightsister figure from the Clone Wars, and it didn't take too much work to adapt it to 'Joe style articulation.
I'm not sure yet if Shadow Weaver is an individual or the name of a branch of the Arashikage clan, but either way I see their role as an illusionist. They rely on sleight of hand and deception to build a false aura of super natural mystique around the Ninja Clan, using these tricks to instill fear and confusion in their enemies. I borrowed the name from the Masters of the Universe character when I realized there was strong visual similarity, and of course "Shadow" is a component of the translated name of the clan.
Nightsister - Base Figure
X-23 - Hips and Upper Legs
Rabe - Head (sculpted mask)